(π x Length x Diameter2)4
by Aporiaqualia
Summary: (Major Spoilers for KR Build Ep 30/31) It's for scientific reasons, I swear.


this was a PWP written as a joke from a friend's server but i decided to expand it further.  
Shoutout to Orange God and Grape (you know who you are lmaooo)

Disclaimer: I do not own Kamen Rider Build and its characters. I'm having a good time thinking about dumb shit about them though.

At Nascita, there was an tense atmosphere that loomed over the lab. Misora was fast asleep, tired from today's events and Sawa went home soon after. The only ones awake were two idiots; an genius idiot named Sento, and a complete idiot, named Ryuga.

Sento slumped into the chair near his computer, thinking about the statement that Bloodstalk made about his friend.

"Alien... huh?" he muttered. Ryuga felt weird. His partner would usually be up and about, writing (or bullshitting) a new formula so he can counter Bloodstalk and Rogue.

But today felt different, not right.

The brunet walked over to Sento and waved his hand in front of the zoned out genius. "Oi, Sento." It didn't work. Ryuga shook his shoulder and Sento finally snaps out of his daydream. "Sorry... was thinking of what Stalk said about you."

"Oh..." Ryuga felt guilty. "Sorry. Didn't think you were... you know, bothered by that..."

Sento only looked away, trying to hold back the countless questions he had for his partner-in-arms. "I was mostly curious about your Martian powers, that's all."

Ryuga jumped onto Sento, tackling him to the ground to the surprise of the scientist. "So you wanna know what I can probably do with these alien powers, huh...?" The black-haired Rider only nodded quickly as a response, and Ryuga smirked as he straddled Sento.

"For starters... my body is mostly human..." Ryuga took off his notable jacket and his T-shirt, his built body being revealed. He gave a slight teasing stripshow for Sento, running his hands all over his body quite clumsily. "... save for my dick." he gasped out as he ran his hand over his growing bulge, and unzipping his jeans. A noticable erection was straining against the blue and yellow boxers. He slipped it off, showing his tentacle cock to another person that wasn't an unfamiliar scientist.

Sento was speechless seeing the dick of his best friend. It resembled a reptilian hemipenis, but it had the length and liveliness of octopus limbs. He counted, and it had five tendrils.

"What?" Ryuga asks as he presents his array of slithering tentacles of a dick proudly to Sento's face.

"I take that you never paid attention to Health class," Sento commented non-chalantly, trying to keep his cool by insulting but was obviously blushing from the mere view of it. He could feel the blood rushing south. "Hey, Banjou..." he whispered, not trusting his voice.

"Hm?" Ryuga tilted his head.

"Could you get off me and sit on the floor?" Ryuga wanted to comment but decided not to and comply to Sento's word. He got up from Sento's hips and sat on the cold floor of the lab, the contact making Ryuga hiss a bit. What he did not expect was Sento's head near his crotch, grasping the tendrils gently.

"... You're always full of mystery, Banjou..." the black-haired man softly remarked as he tenderly stroked each tentacle. Ryuga's body couldn't help it and let the tentacles wrap around Sento's fingers, like as if he wanted to hold his hand.

"You make me want to know more about you..." a shy lick to the tip of one of the tentacles came after, causing Ryuga to jolt and the tentacles were getting more engorged and get bigger. Seeing his body reacting to such, Sento made his decision to slide one of the tentacles into his mouth and sucked on it. The scientist's hand rubbed the other four and giving pleasure to Ryuga. The brunet tried his best not to thrust into Sento's mouth.

"Ah- Sento-! I'm... I'm sorry- My body isn't-!" was what Ryuga said as all of his tentacles slid into Sento's mouth and he gripped a handful of black hair, thrusting upwards. Sento's mouth was mercilessly fucked and he could feel the tentacles violating his throat. The dragon Rider grunted and came instantaneously into Sento's mouth. He fell onto his back, trying to recover form his orgasm as the scientist tried not to choke or spit out the odd cum in his mouth.

"That was fun, Banjou." he said as he swished the alien semen in his mouth. "We should do this more often."


End file.
